<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <title>Document</title>
</head>
<body>
    <script>
        function getColor(flag=true){
            if(flag){
                let str='#'
                let arr=['0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f']
                for(let i=0;i<6;i++){
                    let random=Math.floor(Math.random()*arr.length)
                    str+=arr[random]
                }
                return str
            }else{
                let r=Math.floor(Math.random()*256)
                let g=Math.floor(Math.random()*256)
                let b=Math.floor(Math.random()*256)
                return `rgb(${r},${g},${b})`
            }
        }
        
        console.log(getColor(true))
    </script>
</body>
</html>